You wouldn’t think a house mouse would be any trouble on an island in the middle of the ocean, and you might be right in that assumption. But you also wouldn’t have expected the mouse to evolve so quickly as to have grown to two to three times its usual size and to have developed a taste for bird chicks. That’s exactly what has happened on Gough Island—the same absence of predators that has allowed sea birds to thrive unharmed has allowed the giant mouse population to balloon to nearly three quarters of a million. The mice attack at night, gnawing through nests and straight into the living chicks, who are essentially helpless mounds of fat. Their parents are equally unable to fight them off, having no biological experience with predators. The mice (now thought to the largest species of mouse anywhere) if left unchecked, are poised to bring several of these most rare bird species to extinction. The only current plan to attempt an eradication involves dropping thousands of tons of rat poison from the air in the hopes that the mice will take the bait and retreat to their nests to die. New Zealand has had success controlling rodent populations this way on several of its islands. Via The Guardian
